JP2003218164A - Electronic component bonding apparatus and electronic component bonding tool - Google Patents

Abstract

An object of the present invention is to provide an electronic component bonding apparatus and an electronic component bonding tool that can efficiently utilize vibration without causing damage to the electronic component. SOLUTION: In a bonding tool for bonding electronic parts by ultrasonic vibration, a vibrator 17 is provided at an end.
Is provided at a center position of the rib 15c of the horn 15 which is supported by the two ribs 15c and is supported by the two ribs 15c. 31. By driving the vibrator 17 to apply longitudinal vibration to the horn 15, the phase of the vertical expansion and contraction vibration of the horn 15 generated due to the longitudinal vibration matches the phase of the bending vibration generated in the convex portion 30. The phases are set to be the same, and the displacement of the stretching vibration at the side ends A and B of the joining action portion 31 is offset by the bending displacement caused by the bending vibration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component bonding apparatus and an electronic component bonding tool for bonding an electronic component such as a bumped electronic component to a surface to be bonded such as an electrode of a substrate.

[0002]

2. Description of the Related Art As a method of bonding an electronic component to a surface to be bonded such as an electrode of a substrate, a method using ultrasonic pressure welding is known. In this method, ultrasonic vibration is applied to the electronic component while pressing the electronic component against the surfaces to be joined, and the joint surfaces are caused to vibrate slightly to generate friction, thereby bringing the joint surfaces into close contact with each other. The bonding tool used in this method has a horn that is an elongated rod body that transmits the vibration of the ultrasonic oscillator, which is the vibration source, to the electronic component. Electronic components are bonded to the surfaces to be joined by pressure while applying load and vibration.

The joining action portion is generally provided at a portion corresponding to an antinode having the largest amplitude in the horn, and at an end portion of a convex portion protruding from the horn in order to avoid interference with other electronic parts and the like. . Then, bending vibration is generated by the vibration (longitudinal vibration) transmitted to the convex portion via the horn, the amplitude at the contact surface with the electronic component is enlarged, and the electronic component is bonded.

[0004]

However, when the above-mentioned bonding tool is applied to a large-sized electronic component, the following inconvenience occurs. That is, in the bending vibration of the convex portion, not only the displacement in the direction parallel to the contact surface (horizontal direction) but also the displacement in the direction orthogonal to the contact surface (vertical direction) occurs. Since this displacement increases as the width dimension of the contact surface of the joining action portion with the electronic component increases, the vertical displacement cannot be ignored in a bonding tool for a large-sized electronic component. It becomes the size.

As a result, in the bonding process, not only the horizontal displacement but also the vertical load is repeatedly applied to the electronic component, causing damage to the electronic component. As described above, the conventional bonding tool has a problem that parts may be damaged during bonding if the vibration is effectively used.

Therefore, an object of the present invention is to provide an electronic component bonding apparatus and an electronic component bonding tool which can efficiently utilize vibration without damaging the electronic component.

[0007]

According to a first aspect of the present invention, there is provided an electronic component bonding apparatus for crimping an electronic component onto a surface to be joined while applying load and vibration to the electronic component. A bonding tool that comes into contact with the electronic component and a pressing unit that presses the bonding tool against the electronic component are provided. The bonding tool includes a horizontally long horn supported by a fixing portion at both ends, and a horn with respect to the horn. A vibrator for applying a longitudinal vibration in a first direction along the longitudinal direction of the second horn, and a second horn at a substantially central position of the fixing portion, the horn being substantially orthogonal to the first direction.
In the second direction of the horn, which is caused by the longitudinal vibration, including a convex portion provided in a protruding manner in a direction and a joining action portion provided at a convex end of the convex portion and abutting against the electronic component. The phase of the vibration waveform of the stretching vibration is the same as the phase of the vibration waveform of the bending vibration generated in the convex portion due to the longitudinal vibration.

An electronic component bonding apparatus according to a second aspect of the present invention is an electronic component bonding apparatus for crimping an electronic component onto a surface to be joined while applying load and vibration to the electronic component, and abutting the electronic component. A bonding tool and a pressing unit that presses the bonding tool against the electronic component are provided. The bonding tool includes a horizontally long horn supported by a fixing portion at both ends, and a horn extending in the longitudinal direction of the horn with respect to the horn. A vibrator that imparts longitudinal vibration in a first direction, a convex portion that is provided at a substantially central position of the fixed portion so as to project from the horn in a second direction that is substantially orthogonal to the first direction, and the convex shape. A joining action portion provided on a convex end of the joining portion that abuts the electronic component, the first joining action portion being caused by stretching vibration in a second direction of the horn caused by the longitudinal vibration. The displacement at both end portions along the direction, and so as to offset the displacement in the second direction of the two side portions due to the bending vibration generated in the convex portions due to the vertical vibration.

An electronic component bonding tool according to a third aspect of the present invention is an electronic component bonding tool for crimping an electronic component onto a surface to be joined while applying load and vibration to the electronic component, and is supported by both ends by a fixing portion. A horizontally elongated horn, a vibrator that imparts longitudinal vibration to the horn in a first direction along the longitudinal direction of the horn, and a substantially central position of the fixing portion from the horn to be substantially orthogonal to the first direction. Of the horn generated due to the longitudinal vibration, including a convex portion provided in a protruding manner in the second direction, and a joining action portion provided at a convex end of the convex portion and contacting the electronic component. The phase of the vibration waveform of the stretching vibration in the second direction is set to be the same as the phase of the vibration waveform of the bending vibration generated in the convex portion due to the vertical vibration.

An electronic component bonding tool according to a fourth aspect of the present invention is an electronic component bonding tool for crimping an electronic component onto a surface to be joined while applying load and vibration to the electronic component, and is supported by both ends by a fixing portion. A horizontally elongated horn, a vibrator that imparts longitudinal vibration to the horn in a first direction along the longitudinal direction of the horn, and a substantially central position of the fixing portion from the horn to be substantially orthogonal to the first direction. Of the horn generated due to the longitudinal vibration, including a convex portion provided in a protruding manner in the second direction, and a joining action portion provided at a convex end of the convex portion and contacting the electronic component. The displacement at both end portions of the joining action portion along the first direction due to the stretching vibration in the second direction is the second direction of the both end portions due to the bending vibration generated in the convex portion due to the longitudinal vibration. By displacement to It was way.

According to the present invention, the expansion and contraction displacement in the second direction at the side end portion of the joining action portion of the horn due to the longitudinal vibration imparted to the horn by the vibrator causes the expansion of the convex portion due to the longitudinal vibration. By offsetting the displacement in the second direction due to bending vibration, the vertical displacement of the joint action part that abuts the electronic component can be minimized, and the vibration can be efficiently used without causing damage to the electronic component. can do.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. 1 is a front view of an electronic component bonding apparatus according to an embodiment of the present invention, FIG. 2A is a perspective view of an electronic component bonding tool according to an embodiment of the present invention, and FIG. FIG. 3 is a partial top-down inverted perspective view of a bonding tool for an electronic component according to an embodiment of the invention, FIG. 3 is a front view of a bonding tool for an electronic component according to an embodiment of the present invention, and FIG. 4 is a view of an embodiment of the present invention. FIG. 5 is an enlarged front view of a convex portion of a bonding tool for an electronic component, FIG. 5 is an explanatory view of a deformed state of the bonding tool for an electronic component when vibration is applied, and FIG. 6 is an embodiment of the present invention. It is explanatory drawing of the vibration measurement of the bonding tool of the electronic component of the form.

First, the overall structure of a bonding apparatus for electronic components will be described with reference to FIG. Reference numeral 1 denotes a support frame, on the front surface of which a first elevating plate 2 and a second elevating plate 3 are vertically movable. A cylinder 4 is mounted on the first lifting plate 2, and a rod 5 of the cylinder 4 is connected to the second lifting plate 3. A bonding head 10 is attached to the second lift plate 3. A Z-axis motor 6 is provided on the upper surface of the support frame 1. Z-axis motor 6 has vertical feed screw 7
To rotate. The feed screw 7 is screwed into a nut 8 provided on the back surface of the first elevating plate 2. Therefore, when the Z-axis motor 6 is driven and the feed screw 7 rotates, the nut 8 moves up and down along the feed screw 7, and the first lifting plate 2 and the second lifting plate 3 are moved.
Also moves up and down.

In FIG. 1, a substrate 46 whose upper surface is a surface to be joined of an electronic component is placed on a substrate holder 47,
The substrate holder 47 is placed on the table 48. The table 48 is a movable table, and horizontally moves the substrate 46 in the X direction and the Y direction to position the substrate 46 at a predetermined position. The table 48 is the substrate 4 for the electronic component 40.
It is a positioning means for moving the 6 relatively.

Reference numeral 42 denotes a camera, which is a uniaxial table 43.
Is attached to. A lens barrel 44 extends forward from the camera 42. The camera 42 is moved forward along the uniaxial table 43, and the tip end of the lens barrel 44 is positioned between the bumped electronic component 40 and the substrate 46, which are held by being attracted to the lower surface of the bonding tool 14 as shown by the chain line. In that state, the positions of the electronic component 40 and the substrate 46 are observed by the camera 42.

A recognition unit 53 recognizes the images of the electronic component 40 and the substrate 46 picked up by the camera 42 and detects their positions. Reference numeral 50 denotes a main control unit that controls the vertical movement of the Z-axis motor 6, that is, the bonding head 10 via a motor drive unit 51, and positions the table 48, that is, the substrate 46, via the table control unit 52. Further, the main control unit 50 calculates the positional deviation between the electronic component 40 and the substrate 46 in the horizontal plane from the positions detected by the recognition unit 53, and drives the table 48 so as to correct the positional deviation. Further, the load control unit 54 and the suction device 56 are connected to the main control unit 50.

The cylinder 4 as the pressing means is connected to the main controller 50 via the load controller 54, and the projection force of the rod 5 of the cylinder 4, that is, the bonding tool 14 is connected.
Thus, the pressing load for pressing the bumps of the electronic component 40 against the substrate 46 is controlled. The suction device 56 receives the command from the main control unit 50, and the electronic component 40 by the bonding tool 14
Suction and release of suction. The vibrator 17 is connected to the main control unit 50 via the ultrasonic vibrator driving unit 55, and the vibrator 17 is driven by the ultrasonic vibrator driving unit 55 in accordance with a command from the main control unit 50. Ultrasonic vibration is applied to the bonding tool 14. At this time, the vibration of the bonding tool 14 is in a resonance state, and the phase difference between the voltage and the current applied to the vibrator 17 is almost zero.

A holder 12 is connected to the lower end of the main body 11 of the bonding head 10. A block 13 is attached to the holder 12, and a bonding tool 14 is fixed to the block 13. The protrusion 13 a on the side of the block 13 is connected to the suction device 56. Protrusion 13a
A suction pad 19 is provided on the suction pad 56, and the suction device 56 can suck and hold the electronic component 40 by bringing the suction pad 19 into contact with the horn 15 as described later.

The bonding tool 14 will be described below with reference to FIGS. FIG. 2A shows block 1
FIG. 2B is a perspective view of the bonding tool 14 removed from FIG. 3 obliquely from above, and FIG. 2B partially shows the horn 15 in a state where the bonding tool 14 is turned upside down. Further, FIG. 3 shows a front view of the bonding tool 14 and a graph of the amplitude of standing wave vibration induced in the horn 15 by the vibrator 17.

As shown in FIG. 2A, the bonding tool 14 is mainly composed of a horizontally long horn 15. The horn 15 is made of a metal material (for example, stainless steel, aluminum, titanium, etc.) and is a rod-shaped body having a rectangular cross section with a height dimension H and a width dimension W. One side end of the horn 15 has a side end portion. The vibrator 17 is attached. The dimension of H or W may be changed continuously or stepwise along the longitudinal direction of the horn. As a result, it is possible to adjust the vibration applied by the vibration applying means so that the vibration is expanded or reduced in the horn 15. By driving the vibrator 17, the first direction (arrow a) along the longitudinal direction of the horn 15 is driven.
Longitudinal vibration is applied in the (direction). Therefore, the vibrator 17 serves as a vibration applying unit that applies vibration in the first direction along the longitudinal direction of the horn 15.

On both side surfaces 15b of the horn 15, ribs 15c are respectively provided integrally with the horn 15 at two locations in a centered arrangement. The dimension between the two ribs 15c is set to be equal to the half wavelength (L / 2) of the longitudinal vibration imparted by the vibrator 17 in order to minimize the vibration damping by fixing the vibration component. (Fig. 3
reference). It should be noted that the dimension is not limited to L / 2, as long as the vibration damping is acceptable.

The rib 15c is provided so as to project outward from the horn 15, and the mounting hole 15 provided in the rib 15c is provided.
By inserting a bolt (not shown) into d and fastening it to the block 13, the horn 15 is fixed to the block 13 in a double-supported state. That is, the four ribs (two sets) 15 c are fixing portions that fix the horn 15 to the block 13.

In fixing the horn 5, since the four ribs 15c are arranged symmetrically with respect to the center point of the horn 15, the bonding tool 14 can be fixed to the block 13 in a well-balanced manner, and the pressing means can be used. The load applied to the horn 15 can be supported with good balance. The number of ribs 15c is not limited to four,
For example, two pieces may be provided above the node of the horn 15. The point is that the load applied to the horn 15 can be supported in a well-balanced manner, and the number of ribs is not limited as long as this is the case. Further, the structure is such that the bolt does not project from the lower surface of the horn 15 when the bolt is inserted into the mounting hole 15d and fastened, and the horn 15 can be fixed without interfering with electronic components on the substrate during bonding. There is.

At a substantially central position of the two sets (four) of ribs 15c, the convex portion 30 is in a second direction (arrow b) orthogonal to the first direction.
Direction). It is preferable that the material of the convex portion 30 is the same as that of the horn 15 because it can be integrally formed with the horn 15, but it may be a different material. When different materials are used, the shape and size of the convex portion 30 are set in consideration of the differences in density, Young's modulus and Poisson's ratio with the material of the horn 15.

At the convex end of the convex portion 30, a joint acting portion 31 that comes into contact with the electronic component 40 to be joined is provided.
The bump of the electronic component 40 is pressed against the substrate 46 by applying a pressing load to the bonding tool 14 while the electronic component 40 is in contact with the bonding action portion 31. Then, in this state, the vibrator 17 is driven to drive the horn 15.
By applying longitudinal vibration to the electronic component 40,
6 is crimped by load and vibration. At this time, the convex portion 3
Since 0 is located in the center of the four ribs 15c,
Even when a large component requiring a large pressing load is targeted, a uniform pressing state is realized.

As shown in FIG. 2B, the joining action portion 31
An adsorption hole 31b is opened in the bonding action surface 31a on the lower surface of the. As shown in FIG. 3, the suction hole 31b is provided in the horn 15.
The suction holes 16c opened in the upper surface 15a of the horn 15 via the suction passages 16a and 16b formed inside (see FIG. 2).
(See (a)).

In the state where the bonding tool 14 is fixed to the block 13, the suction pad 19 provided on the protrusion 13a comes into contact with the upper surface 15a of the horn 15 (see FIG. 1), so that the suction hole 31b has a suction path 16a. , 16
It communicates with the suction pad 19 via b and the suction hole 16c. Therefore, the suction device 5 connected to the suction pad 19
By driving 6 (see FIG. 1) to suck air,
Vacuum suction can be performed from the suction holes 31b, and the electronic component 40 can be vacuum-suctioned and held on the bonding surface 31a. That is, the convex portion 30 presses the electronic component 40 against the substrate 46 and contacts the upper surface of the electronic component 40 to contact the electronic component 4
It also has a function as an adsorber that adsorbs and holds 0.

On the opposite side of the horn 15 from the convex portion 30 in the longitudinal direction, there is provided a vibration balance portion 32 having a shape substantially the same as that of the convex portion 30. Vibration balance section 32
It is preferable that the material of the same is the same material as the horn 15 because it can be integrally formed with the horn 15, but different materials may be used.
In the case of different materials, the shape and dimensions of the vibration balance portion 32 are set in consideration of the differences in density, Young's modulus and Poisson's ratio with the material of the horn 15. The vibration balance unit 32 is
In the bonding tool 14, it is provided mainly to maintain the vertical vibration balance of the horn 15 by maintaining the mass balance, and the balance is achieved by the position, shape and size of the through hole 32a penetrating in the thickness direction of the horn. The amount can be adjusted. The vibration balance section 32 makes the vibration distribution and mass distribution of the horn 15 substantially symmetrical with respect to the central axis in the first direction, and ensures uniform vibration transmission.

Next, the vibration characteristics of the horn 15 will be described. The ultrasonic transducer driving unit 55 causes the transducer 17 to have an appropriate frequency according to the horn 15 (a frequency that brings the horn 15 into a resonance state is sufficient, but is preferably 40 kHz or more and 70 kHz or less, and further about 60 kHz. Is desirable for the bonding of electronic parts.) And the longitudinal vibration in the first direction is applied to the horn 15 to create a resonance state, so that the horn 15 receives a standing wave vibration as shown in the graph of FIG. Occur. That is, in the standing wave vibration of the horn 15, the position of the rib 15c is a node having almost no horizontal displacement, and the position of the convex portion 30 located at the center of the rib 15c corresponds to the antinode where the horizontal amplitude is maximum. To do. It is desirable that the position of the convex portion 30 coincides with the position of the antinode of this standing wave vibration, but as long as it is located substantially in the center of the rib 15c that fixes the horn 5, the standing wave is not generated. It may be slightly displaced from the position of the antinode of vibration.

Then, the vibration of the convex portion 30 causes the bonding action surface 31.
It is transmitted to the electronic component 40 via a. This electronic component 4
In transmitting the vibration to 0, not only the longitudinal vibration imparted to the horn 15 by the vibrator 17 but also the bending vibration induced in the convex portion 30 by the longitudinal vibration of the horn 15 is superimposed and transmitted as described later. It

Next, the detailed shape of the convex portion 30 will be described with reference to FIG. As shown in FIG. 4, on the lower surface of the horn 15, a protruding portion 30 having a predetermined protruding height dimension D and a root width dimension B1 is formed. The convex portion 30 has a base width dimension B1.
The convex end width dimension B2 in which the bonding action portion 31 is provided is smaller than the lower constricted shape, and the convex end width dimension B2 is determined according to the size of the electronic component 40 to be bonded.

By setting the shape of the convex portion 30 to the downward constricted shape as described above, the convex portion 3 is formed at the time of bonding.
It is possible to avoid the interference between 0 and the already mounted components on the substrate 46. Further, by processing only the joining action portion 31 and the convex edge width dimension B2 in accordance with the target electronic component, the bonding tool 14 having the same basic shape and dimensions can be used for many kinds of electronic components. .

The protruding height dimension D, the root width dimension B1 and the protruding end width dimension B2 are determined in combination with the height dimension H and the width dimension W of the horn 15 as described later. In the dimension setting example shown in the present embodiment, the root width dimension B
Since 1 is arranged between two sets (4 pieces) of ribs 15c, 1 is set to be smaller than a half wavelength (L / 2). Regarding the height dimension H of the horn 15 in the vicinity of the convex portion 30, the root width dimension B1 is set to be larger than the height dimension H, and the height dimension H is the protruding height dimension. The dimension setting is selected so as to be larger than D.

The joining action portion 31 provided on the convex end of the convex portion 30 is a method of brazing or bolting a plate-like component manufactured according to the size of the target electronic component to the convex portion 30. It is configured to be fixed by joining and fastening with. Brazing as a method of fixing the plate-shaped component can firmly and stably fix it, and if bolting is adopted, it can be easily attached and detached. Further, by using a hard material having excellent wear resistance (for example, cemented carbide) as the material of the plate-shaped component, the component life of the bonding tool 14 can be extended. of course,
The joining action portion 31 that abuts the electronic component 40 may be provided integrally with the convex portion 30. In addition, the joining action portion 31 is replaced by the convex portion 3
Removable with respect to 0, and the convex portion 30 is attached to the horn 1.
It may be detachably attached to the main body. As a result, only the worn portion can be replaced, and the service life of the bonding tool 14 can be further extended.

Next, referring to FIG. 5, the above-described shape
Bonding tool 14 provided with a convex portion 30 having a size
The deformation state when the vibration is applied will be described. Figure 5 (a)
As shown in FIG. 2, by driving the vibrator 17 mounted on the left end of the horn 15 in a state in which the horn 15 is supported on both sides by two sets (4 pieces) of ribs 15c and these two positions are fixed, Longitudinal vibrations in which displacements in opposite directions c and d are alternately repeated are transmitted to the horn 15.

In the state where the horn 15 is vibrating in the horizontal direction by this vibration application, when the displacement given by the vibrator 17 is the displacement to the right as shown in the direction of arrow c, as shown in FIG. 5 (b). In addition, as the outer shape of the horn 15, the entire horn 15 slightly moves to the right along the first direction, and inside the horn 15, different deformation behavior is exhibited on the right side and the left side. That is, since the horn 15 is fixed at the position of the rib 15c, the horn 15
In the left-hand half, deformation occurs in the direction compressing from both sides toward the position of the rib 15c, and in the right-hand half whose tip is a free end, deformation occurs in the direction pulling the position of the rib 15c from both sides. At this time, the central position 15e of the horn 15
Has been displaced to the left, and therefore the joining action portion 31 has been horizontally displaced to the left.

Due to the compressive deformation and tensile deformation of the horn 15 in the first direction, expansion and contraction displacement is generated in the second direction orthogonal to the first direction according to the Poisson's ratio peculiar to the material of the horn 15. The expansion / contraction displacement in the second direction is caused by the horn 15
The displacement is almost zero at the center position of the, and the expansion and contraction displacement is maximized at the position of the rib 15c which is the fixed position of the horn 15. As a result, the first of the joining action portion 31
Both ends along the direction (points A and B shown in FIG. 5 (a))
At the position corresponding to, expansion / contraction displacements ΔH (a) and ΔH (b) in which the directions of compression and tension are always opposite are generated.

By reversing the direction of the vibration displacement applied from the vibrator 17 to the horn 15, the directions of the expansion / contraction displacements ΔH (a) and ΔH (b) are also reversed. That is,
Due to the vertical vibration applied to the horn 15 by the vibrator 17, the horn 15 generates a stretching vibration in the second direction. In addition, when the symmetry of the horn 15 is maintained, the magnitudes of the absolute values of the expansion / contraction displacements ΔH (a) and ΔH (b) are substantially equal.

FIG. 5 (c) shows the displacement due to bending vibration induced in the convex portion 30 by this longitudinal vibration. The timing shown in FIG. 5B is a state in which the center position 15e of the horn 15 is displaced to the left by the vertical vibration as described above, and at this time, the center position 15e is returned in the opposite direction (rightward direction). Acceleration (arrow e) is acting. When the acceleration in the right direction is applied, the inertial force (arrow f) in the direction opposite to the acceleration direction to the horn 15 and the direction (right direction in the right direction) between the convex portion 30 and the horn 15 are applied. ) To act on. The restoring force is generated by the deformation of the convex portion 30.

Due to the inertial force and the restoring force, a bending moment M acts on the convex portion 30 and the lower surface of the convex portion 30 is shown in FIG.
Bending deformation that causes displacement as in (c) occurs.
Then, as the alternating acceleration due to the vertical vibration of the horn 15 acts, the inertial force and the restoring force act on the convex portion 30 at the same vibration frequency as the vertical vibration, and the vibration that induces the forced vibration on the convex portion 30 is generated. Become power.

That is, the horn 15 is moved by the vibrator 17.
The above-mentioned vibration force acts on the convex portion 30 due to the vertical vibration applied to the. Then, due to this exciting force, the convex portion 30
Vibrates with a vibration characteristic as a cantilever having a fixed end on the horn 15 and a joining action portion 31 as a free end, and the free end vibrates due to bending vibration induced by the vibration transmitted from the horn 15. As a result, not only the displacement in the first direction along the longitudinal direction of the horn 15 but also the displacement in the second direction orthogonal to the first direction are induced in the joining action portion 31 of the convex portion 30, and Vertical displacements ΔD (a) and ΔD (b) occur at the side ends A and B of the.

Here, as shown in FIG. 4, the protrusion height dimension D
Is the convex portion 3 so that it is smaller than the root width dimension B1.
Since the protruding shape / dimension of 0 is set, the natural frequency of bending vibration of the convex portion 30 is extremely high. Therefore, the convex portion 3 is generated by the vibration force given by the vibrator 17.
In the bending vibration (forced vibration) induced by 0, the convex portion 30 exhibits a vibration behavior synchronized with the longitudinal vibration of the vibrator 17.

Therefore, the phase of the vibration waveform of the stretching vibration in the second direction generated due to the longitudinal vibration of the horn 15 is the vibration waveform of the bending vibration generated in the convex portion 30 due to this longitudinal vibration. Is always in the same phase as the phase (arrows v1, v2 shown in FIG. 6).
(When the phase is compared with the direction as the positive direction). That is, the deformations shown in FIGS. 5B and 5C always occur in synchronization. Therefore, when the vibrator 17 is driven and the vibration of the horn 15 is in a steady state, the deformation state of the joining action portion 31 is obtained by overlapping FIGS. 5B and 5C as shown in FIG. 5D. It is expressed in the combined deformed state.

Expansion and contraction displacement ΔH generated in the horn 15
(A) and ΔH (b) and displacements ΔD (a) and ΔD (b) due to bending vibration of the convex portion 30 are always generated in the side end portions A and B of the joining action portion 30 in directions canceling each other. Therefore, as shown in FIG. 5D, the vertical displacement (second direction) of the bonding action surface 31a during bonding is significantly reduced.

This vertical displacement not only contributes to ultrasonic bonding at the time of bonding, but also acts vertically on the electronic component and causes damage, but as described above, it occurs due to longitudinal vibration. The displacement at the side ends A and B due to the vertical stretching vibration of the horn 15 is canceled by the vertical displacement of the side ends A and B due to the bending vibration generated in the convex portion 30 due to the longitudinal vibration. By doing
The vertical displacement can be minimized. Therefore, it is possible to prevent damage to electronic components during bonding and to effectively use the vibration of the vibrator 17.

Here, when determining the shape and size of each part of the bonding tool 14, the expansion and contraction displacements ΔH (a) and ΔH (b) of the horn 15 and the convex portion 3 due to bending vibration are described.
It is desirable to make a detailed setting after quantitatively evaluating the magnitudes of the displacements ΔD (a) and ΔD (b) of 0. This makes it possible to more effectively achieve the purpose of reducing the vertical displacement of the joining action surface 31a.

When the vibration intensity is constant, the expansion and contraction displacement caused by the vibration displacement imparted by the vibrator 17 is the horn 1.
5 is determined by the cross-sectional area of the cross section perpendicular to the first direction (height dimension H × width dimension W). The displacement of the convex portion 30 due to bending is determined by the magnitude of the bending moment M (determined by the magnitude of the inertial force acting on the convex portion 30 and the position of the point of application of the resultant force of the inertial force) and the convex portion 30. Depends on the mechanical rigidity of the above, and is determined by the protruding shape, size, and material of the protruding portion 30.

Therefore, the height dimension H and the width dimension W indicating the cross-sectional shape and dimensions of the horn 15 in the cross section perpendicular to the first direction, and the root width dimension indicating the protruding shape and dimensions of the convex portion 30. By properly setting the combination of B1, convex end width dimension B2, and convex height dimension D, the horn 15
The phase of the vibration waveform of the stretching vibration in the second direction generated due to the vertical vibration is always in phase with the phase of the vibration waveform of the bending vibration generated in the convex portion 30 due to the vertical vibration. And the absolute values of the expansion / contraction displacements ΔH (a) and ΔH (b) at the positions corresponding to the side ends A and B due to the stretching vibration, and the displacement ΔD due to the bending vibration at the side ends A and B due to the bending vibration. The absolute values of (a) and ΔD (b) can be made substantially equal at each corresponding position. Therefore, when the displacement due to the stretching vibration is offset by the displacement due to the bending vibration, the displacement in the opposite direction can almost completely cancel the displacement in the vertical direction, and a more effective offset result can be obtained. .

Shapes and dimensions of the above parts, ΔH (a), ΔH
In order to obtain the correlation between (b), ΔD (a), and ΔD (b), a numerical analysis method such as the finite element method and a method of referring to the actual measurement result obtained by measuring the displacement of the actual bonding tool It is desirable to combine and. By performing such detailed shape / dimension setting, the joining action surface 31
An ideal horizontal vibration with almost no vertical displacement of a can be obtained.

Next, referring to FIG. 6, the above-described shape
The result of actually measuring the vibration state of the bonding tool 14 having the dimension set will be described. As shown in FIG.
With the longitudinal vibration applied to the horn 15, the horn 1
The vertical vibration near the root of the convex portion 30 on the lower surface of 5 (v
1) and horizontal vibration (v2) and vertical vibration (v3) at the side end of the joining action portion 31 were measured.

In this vibration measurement, a laser vibrometer was used, and the above-mentioned three measurement positions were irradiated with laser to obtain a waveform indicating the vibration state. Then, by comparing these waveforms with a reference waveform (here, the applied voltage of the vibrator 17 that gives vibration to the horn 15 is used as the reference waveform), the phases of the vibration waveforms of the vibrations of the respective measurement target parts are compared. be able to. According to this vibration measurement, the vibration waveforms of the vibrations of v1 and v2 have the same phase, that is, the v1 direction and v
When the phases of the vibration waveforms of the same dimension (that is, the phases of the vibration velocity waveforms or the phases of the vibration displacement waveforms) were compared with each other with the two directions as positive directions, it was confirmed that the phases were the same. Further, as a result of comparing the vibration waveforms of v2 and v3, it was confirmed that the amplitude of v3 is 10% or less of the amplitude of v2, and the vertical displacement of the joining action portion 31 is significantly reduced.

[0052]

According to the present invention, the expansion and contraction displacement in the second direction at the side end portion of the joining action portion of the horn due to the longitudinal vibration imparted to the horn by the vibrator causes the convex shape due to the longitudinal vibration. By offsetting the displacement in the second direction due to bending vibration of the part, the vertical displacement of the joining action part that abuts on the electronic component can be suppressed as small as possible, and the vibration can be efficiently performed without causing damage to the electronic component. Can be used well.

[Brief description of drawings]

FIG. 1 is a front view of an electronic component bonding apparatus according to an embodiment of the present invention.

FIG. 2A is a perspective view of a bonding tool for an electronic component according to an embodiment of the present invention. FIG. 2B is a partially upside-down perspective view of a bonding tool for an electronic component according to an embodiment of the present invention.

FIG. 3 is a front view of a bonding tool for electronic components according to an embodiment of the present invention.

FIG. 4 is an enlarged front view of a convex portion of a bonding tool for an electronic component according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of a deformed state when a vibration is applied to a bonding tool for an electronic component according to an embodiment of the present invention.

FIG. 6 is an explanatory diagram of vibration measurement of a bonding tool for electronic components according to an embodiment of the present invention.

[Explanation of symbols]

14 Bonding tool 15 horn 15c rib 17 oscillators 30 convex 31 Joining part 40 electronic components 46 board

Claims (4)

[Claims] 1. A bonding apparatus for an electronic component, wherein an electronic component is pressure-bonded to a surface to be joined while a load and vibration are applied to the electronic component, the bonding tool being in contact with the electronic component, and the bonding tool being the electronic component. And a pressing means for pressing the component, the bonding tool,
A horizontally long horn supported by a fixed part on both sides, a vibrator for applying a longitudinal vibration to the horn in a first direction along the longitudinal direction of the horn, and a horn from the horn at a substantially central position of the fixed part. It is provided with a convex portion provided to project in a second direction substantially orthogonal to the first direction, and a joining action portion provided at a convex end of the convex portion and abutting on the electronic component. The phase of the vibration waveform of the stretching vibration of the horn generated in the second direction in the second direction is the same as the phase of the vibration waveform of the bending vibration generated in the convex portion due to the longitudinal vibration. Bonding device for electronic parts. 2. A bonding apparatus for an electronic component, wherein an electronic component is pressure-bonded to a surface to be joined while applying load and vibration to the electronic component, the bonding tool contacting the electronic component, and the bonding tool being the electronic component. And a pressing means for pressing the component, the bonding tool,
A horizontally long horn supported by a fixed part on both sides, a vibrator for applying a longitudinal vibration to the horn in a first direction along the longitudinal direction of the horn, and a horn from the horn at a substantially central position of the fixed part. It is provided with a convex portion provided to project in a second direction substantially orthogonal to the first direction, and a joining action portion provided at a convex end of the convex portion and abutting on the electronic component. Displacement of both sides of the joining action portion along the first direction due to expansion and contraction vibration of the horn in the second direction caused by bending vibration generated in the convex portion due to this longitudinal vibration. A bonding apparatus for electronic parts, characterized in that the ends are offset by displacement in the second direction. 3. A bonding tool for an electronic component, wherein an electronic component is pressure-bonded to a surface to be joined while applying load and vibration to the electronic component, and a laterally long horn supported on both sides by a fixing portion. On the other hand, a vibrator that applies longitudinal vibration in a first direction along the longitudinal direction of the horn, and a vibrator that is provided at a substantially central position of the fixing portion so as to project from the horn in a second direction that is substantially orthogonal to the first direction. A second horn that is generated due to the longitudinal vibration, including a convex portion and a joining action portion that is provided at a convex end of the convex portion and contacts the electronic component.
A bonding tool for an electronic component, wherein a phase of a vibration waveform of a stretching vibration in a direction is set to be in phase with a phase of a vibration waveform of a bending vibration generated in the convex portion due to the vertical vibration. 4. A bonding tool for an electronic component, wherein an electronic component is pressure-bonded to a surface to be joined while applying load and vibration to the electronic component. On the other hand, a vibrator that applies longitudinal vibration in a first direction along the longitudinal direction of the horn, and a vibrator that is provided at a substantially central position of the fixing portion so as to project from the horn in a second direction that is substantially orthogonal to the first direction. A second horn that is generated due to the longitudinal vibration, including a convex portion and a joining action portion that is provided at a convex end of the convex portion and contacts the electronic component.
The displacement at both end portions of the joining action portion along the first direction due to the stretching vibration in the direction is caused to move in the second direction at the both end portions due to the bending vibration generated in the convex portion due to the longitudinal vibration. A bonding tool for electronic parts, which is characterized by offsetting by displacement.